flattens Get Printable Handwriting Hear It! Say It! Write It! Learn It! Spelling Test Definition verb. To make something flat or level; to press or squeeze something until it becomes even or smooth Example Sentence Sarah uses an iron to flatten her clothes and remove any wrinkles before wearing them. Synonyms levels; smoothes Antonyms bulges Hear It! Say It! Write It! flattens Switch to cursive Start Share with your friends: